#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
bool cmmdc(int a, int b)
{
    while(a>b || b>a)
    {
        if(a>b) a=a-b;
        if(a<b)b=b-a;
    }
    if(a==1)return true;
    return false;
}
int main()
{
    int n;
    int cnt2=0;
    fin>>n;
    int p,q;
    for(p=1;p<=n;p++)
    for(q=p+1;q<=n;q++)
    {
    if(cmmdc(p,q))cnt2++;
    }
    fout<<cnt2*2+1;
    return 0;
}